1. Field of the Invention
The present invention relates to a ceramic dental restoration coloring solution that contains an organic solvent. The purpose for this solvent is to assure the homogeneity of the solution that contains metallic salts. Derivatives of propylene oxide can be used for this purpose. The coloring solution should comprise an organic solvent of 1% to about 5% by weight.
The present invention also relates to a dental restoration coloring solution that contains acid. The more acidic is the solution, the deeper the color penetration will result. Adding an acid will decrease the pH further, prompting an increase in color penetration. An acidic pH level in the range of 1.0 to 3.0 is preferred.
2. Background Discussion
Aesthetics are a very significant factor when evaluating dental restorations. In particular, the translucency and color of a restoration are especially important. When considering ceramic dental restorations, the translucency is an innate optical property of the material. However, the color needs to be added to the ceramic. At present, a coloring solution containing metallic salts is used to color a pre-sintered ceramic body.
When applying color to a ceramic dental restoration, a specific hue, value, and chroma must be present to match the aesthetics of a natural tooth. Therefore, specific metallic salts are chosen to match these colors. Furthermore, the penetration of the coloring solution of the ceramic should be maximized to allow for adjustments to be made on the restoration after final sinter. Should the color solution not penetrate deeply enough into the restoration, any grinding on the surface remove the colored ceramic and reveal the underlying white ceramic.
It should therefore be in the nature of the coloring solutions to produce the particular colors of natural teeth and to sufficiently penetrate the ceramic body. The present invention relates to a coloring solution containing specific metallic salts that not only produce these colors, but also has a chemical disposition to infiltrate the ceramic body thereby ensuring that the color sufficiently penetrates the dental restoration.